The American legal system, as well as some other legal systems around the world, relies heavily on written judicial opinions, the written pronouncements of judges, to articulate or interpret the laws governing resolution of disputes. Each judicial opinion is not only important to resolving a particular legal dispute, but also to resolving similar disputes, or cases, in the future. Because of this, judges and lawyers within our legal system are continually researching an ever-expanding body of past opinions, or case law, for the ones most relevant to resolution of disputes.
To facilitate these searches West Publishing Company of St. Paul, Minn. (doing business as Thomson West) collects judicial opinions from courts across the United States, and makes them available electronically through its Westlaw™ information-retrieval system. (Westlaw is a trademark of Thomson West.) Many of these opinions are published with bibliographic cites or hyperlinks to other opinions, that rely on or criticize various points of law in these opinions. The cites and hyperlinks enable researchers to find printed volumes containing the related opinions or readily access the related opinions electronically over a computer network. The Westlaw system empowers users to search over 100 million documents.
At least one problem the present inventors recognized with this effective and highly successful system is that there are numerous other types of documents, other than opinions, that may be of use to legal researchers, but are frequently overlooked. For example, some users do not take full advantage of the West Key Number™ System, which provides classified summaries of legal points, made in judicial opinions. (West Key Number is a trademark of Thomson West.) The summaries, known as headnotes, are classified into more than 90,000 distinct legal categories, and can be used for a variety of purposes, such as evaluating the relevance of legal opinions to particular legal issues. Others overlook secondary resources, such as American Law Reports (ALR), which includes about 4,000 in-depth scholarly articles, each teaching about a separate legal issue.
Accordingly, the present inventors have recognized a need for improvement of the information-retrieval systems for legal documents.